S4 high idle
01-14-19, 04:28 PM
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S4 high idle
My 87 GXL almost always idles around 1400-2000 RPM, and very rarely at 800. When I bought the car the guy was having some trouble keeping the motor from stalling at idle so he tweaked it a bit and maybe went too far. Normally I'd just turn it down but I'm concerned by how it will sometimes idle at 800, which would be a stall if I turned it down from what it is now. Could this be caused by an O2 leak making it run rich? I have a rusty OEM exhaust system so Im probably leaking somewhere.
01-14-19, 05:15 PM
#2
Could be a number of things, try to isolate the problem. The O2 sensor could be a contributing factor but if it's idling high I would check the throttle position sensor. Calibrate it with a multimeter to 1K ohms at idle if I remember correctly. (S4 NA owner)
If the car is in sorry shape, I'd also inspect all of the engine grounds. I removed all of mine, cleaned the contacts and applied dialectic grease. My idle stabilized and 3800 hesitation disappeared after doing this. Follow writeup by Aaroncake, it has all the info you need.
good luck
If the car is in sorry shape, I'd also inspect all of the engine grounds. I removed all of mine, cleaned the contacts and applied dialectic grease. My idle stabilized and 3800 hesitation disappeared after doing this. Follow writeup by Aaroncake, it has all the info you need.
good luck
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